SARS-CoV nucleoprotein from S. cerevisiae, frozen

Description: Severe acute respiratory syndrome coronavirus (SARS-CoV) recombinant Nucleoprotein (SCoV-rN) expressed in yeast Saccharomyces cerevisiae. UniProtKB sequence accession number: P59595 (NCAP_SARS), expressed with N-terminal His6-tag. It was purified from yeast lysates under native (non-denaturing) conditions using convenient chromatographic techniques. The final product is formulated in PBS (pH 7.4).

Form: Frozen liquid in PBS (pH 7.4).

Safety:  Product 20-S1N-ScB-F contains only yeast expressed proteins that are not infectious or hazard. Contains no plasma or serum of animal origin. No safety precautions are required.

Storage: The product is shipped with dry ice (shipment cost to Europe: 160 €). Store at -80°C for the long term. After thawing may be stored for short-term at 4°C (stable at least 1 week at this temperature). Avoid repeated freeze/thaw cycles.

Concentration: 0.3 mg/ml (Lot dependent).

Image: SDS-PAGE showing SCoV-rN product 20-S1N-ScB-F at approximately 48 kDa (1 μg/lane).


Purity: ~90% pure intact form of SCoV2-rN protein as determined by SDS-PAGE.

Applications: ELISA, other immunoassays, Western blot, SDS-PAGE.

Reactivity of SCoV-rN protein (product 20-S1N-ScB-F) with anti-SARS-CoV-2 IgG in ELISA using Covid-19 positive and negative human sera: this product has been used as a control for SARS-CoV-2 recombinant proteins in ELISA and S1 antigen-based CE-approved commercial IVD tests using the same set of human sera. It has shown very similar results to SARS-CoV-2 recombinant nucleoprotein product due to high degree of similarity (sequence identity of SARS-CoV and SARS-CoV-2 nucleoproteins is >90%). Therefore, SCoV-rN nucleoprotein may also be used for the detection of specific antibodies against SARS-CoV-2. Still, SCoV2-rN showed higher reactivity with specific antibodies in Covid-19 positive sera. Results for sensitivity and specificity are provided in the Table below:

Reference test for Covid-19 positive sera RT-PCR

Analyzed antigens or

serological tests

# 20-S1N-ScB-F) IgG
(from E.coli) IgG
# 20-S2N-ScA-F) IgG
(Sino Biological)
AMP rapid (S1) IgG test Euroimmun ELISA (S1) IgG test
Sensitivity (n=50), correct positives 92.00% 92.00% 92.00% 78.00% 90.00% 90.00%
Specificity (n=150), correct negatives 99.33% 94.00% 99.33% 97.33% 99.33% 98.67%
OD mean for positive sera (n=50) 1,967 1,455 2,502 0,980 N. A. 1,820



Size Catalogue No. Price
100 μg 20-S1N-ScB-F-C 500 € Inquiry / Order